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Hi John,
So focus likely not the cause...
Yep, odd spikes could be a multitude of things but also could be diagnostic of something more... I personally have never had to deal with pinched optics but it is a known issue on some models of these scopes according to my reading.
Plenty of people on these forums would have more experience with this issue or of how to test for it but the best way I would think would be to check the defocus star shape across your FOV. Misshapen or irregular doughnuts (triangular in this case given the mirror support structure or mirror clamps) could be suggestive of this.
Some have reported this is caused by the edge mirror retaining clamps being over tightened at the factory. The problem is solved by simply adjusting or loosening them. Worthwhile reading up on the issue. This can really confound collimation.
Tim
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